import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.function.Consumer;

/**
 * ClassName: ${NAME}
 * Package:
 * Description:
 *
 * @Author BCXJ
 * @Create 2024/11/25 23:59
 * @Version 1.0
 * @Since 1.0
 */
public class Main {
    public static void main(String[] args) {
        HashSet<Integer> set1 = new HashSet<>();
        HashSet<Integer> set2 = new HashSet<>();
//        set1.add(1);
//        set1.add(2);
//        set1.add(3);
//        set1.add(4);
//        set1.add(5);
        set1.add(11);
        set1.add(112);
        set1.add(13);

        set2.add(2);
        set2.add(4);
        set2.add(6);

        ArrayList<Integer> l3 = new ArrayList<>();
        l3.add(2);
        l3.add(2);
        l3.add(6);
        l3.add(null);
        l3.add(null);
        System.out.println(l3);
        set1.retainAll(set2);
        set1.retainAll(l3);

        System.out.println("set1：" + set1);
        System.out.println("set2：" + set2);

        System.out.println(1 + "123");

    }


    public static Consumer<Integer> add() {
        int y = 20;
        Consumer<Integer> function = x -> System.out.println("res = " + (x + y));
        return function;
    }
}

interface A {
    void ss() throws Exception;
}

class B implements A {

    @Override
    public void ss() {
        System.out.println("XXXXXXX");
    }
}